全文获取类型
收费全文 | 4309篇 |
免费 | 542篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 41篇 |
儿科学 | 127篇 |
妇产科学 | 121篇 |
基础医学 | 649篇 |
口腔科学 | 292篇 |
临床医学 | 579篇 |
内科学 | 784篇 |
皮肤病学 | 44篇 |
神经病学 | 274篇 |
特种医学 | 157篇 |
外科学 | 575篇 |
综合类 | 107篇 |
一般理论 | 8篇 |
预防医学 | 447篇 |
眼科学 | 43篇 |
药学 | 309篇 |
中国医学 | 1篇 |
肿瘤学 | 307篇 |
出版年
2022年 | 25篇 |
2021年 | 64篇 |
2020年 | 52篇 |
2019年 | 86篇 |
2018年 | 89篇 |
2017年 | 92篇 |
2016年 | 78篇 |
2015年 | 91篇 |
2014年 | 102篇 |
2013年 | 122篇 |
2012年 | 202篇 |
2011年 | 203篇 |
2010年 | 130篇 |
2009年 | 115篇 |
2008年 | 175篇 |
2007年 | 175篇 |
2006年 | 173篇 |
2005年 | 202篇 |
2004年 | 168篇 |
2003年 | 159篇 |
2002年 | 171篇 |
2001年 | 167篇 |
2000年 | 137篇 |
1999年 | 163篇 |
1998年 | 80篇 |
1997年 | 69篇 |
1996年 | 81篇 |
1995年 | 67篇 |
1994年 | 47篇 |
1993年 | 44篇 |
1992年 | 123篇 |
1991年 | 101篇 |
1990年 | 92篇 |
1989年 | 110篇 |
1988年 | 96篇 |
1987年 | 88篇 |
1986年 | 67篇 |
1985年 | 65篇 |
1984年 | 45篇 |
1983年 | 42篇 |
1982年 | 29篇 |
1981年 | 26篇 |
1980年 | 21篇 |
1979年 | 48篇 |
1978年 | 34篇 |
1977年 | 41篇 |
1976年 | 35篇 |
1975年 | 31篇 |
1971年 | 23篇 |
1970年 | 29篇 |
排序方式: 共有4865条查询结果,搜索用时 15 毫秒
101.
Catharine Chambers Shirley Chiu Allison N. Scott George Tolomiczenko Donald A. Redelmeier Wendy Levinson Stephen W. Hwang 《Community mental health journal》2014,50(5):553-559
The purpose of this study was to estimate the prevalence of mental health problems among a representative sample of homeless women with and without dependent children and determine if the effects of risk factors for mental health are modified by the presence of dependent children. Homeless women (n = 522) were recruited in 2004–2005 from shelters and meal programs in Toronto, Canada. Linear and logistic regression was performed to identify factors associated with mental health status. Poor mental health was associated with low perceived access to social support, physical/sexual assault in the past 12 months, presence of a chronic health condition, and presence of a drug use problem in the past month. Efforts to improve mental health in this population will need to address the associated problems of victimization, substance abuse, and lack of social supports. 相似文献
102.
Combs CE Fuller K Kumar H Albert AP Pirianov G McCormick J Locke IC Chambers TJ Lawrence KM 《The Journal of endocrinology》2012,212(2):187-197
This study investigated the role of urocortin (UCN), a member of the corticotrophin-releasing factor (CRF) family of peptides, in osteoclast maturation and function. We found that 10(-7)?M UCN significantly (P<0.05) suppressed osteoclast differentiation from bone marrow precursor cells in culture and reduced the expression of several osteoclastic markers. Furthermore, UCN potently suppressed osteoclast bone resorption, by significantly inhibiting both the plan area of bone resorbed by osteoclasts and actin ring formation within osteoclasts at 10(-9)?M (P<0.05), with complete inhibition at 10(-7)?M (P<0.001). UCN also inhibited osteoclast motility (10(-7)?M) but had no effect on osteoclast survival. Osteoclasts expressed mRNA encoding both UCN and the CRF receptor 2β subtype. Pre-osteoclasts however, expressed CRF receptor 2β alone. Unstimulated osteoclasts contained constitutively active cation channel currents with a unitary conductance of 3-4?pS, which were inhibited by over 70% with UCN (10(-7)?M). Compounds that regulate calcium signalling and energy status of the cell, both crucial for osteoclast activity were investigated. The non-selective cation channel blockers, lanthanum (La(3)(+)) and gadolinium (Gd(3)(+)), inhibited actin ring formation in osteoclasts, whereas modulators of voltage-dependent Ca(2)(+) channels and K(ATP) channels had no effect. These findings show for the first time that UCN is a novel anti-resorptive molecule that acts through a direct effect on osteoclasts and their precursor cells. 相似文献
103.
ILR Genetics Consortium Emerging Risk Factors Collaboration Sarwar N Butterworth AS Freitag DF Gregson J Willeit P Gorman DN Gao P Saleheen D Rendon A Nelson CP Braund PS Hall AS Chasman DI Tybjærg-Hansen A Chambers JC Benjamin EJ Franks PW Clarke R Wilde AA Trip MD Steri M Witteman JC Qi L van der Schoot CE de Faire U Erdmann J Stringham HM Koenig W Rader DJ Melzer D Reich D Psaty BM Kleber ME Panagiotakos DB Willeit J Wennberg P Woodward M Adamovic S Rimm EB Meade TW Gillum RF Shaffer JA 《Lancet》2012,379(9822):1205-1213
104.
105.
106.
James R. Walsh Daniel C. Chambers Rebecca J. Davis Norman R. Morris Helen E. Seale Stephanie T. Yerkovich Peter M.A. Hopkins 《Clinical transplantation》2013,27(4):E504-E511
Lung transplant recipients report reduced exercise capacity despite satisfactory graft function. We analysed changes in lung function, six‐min walk distance (6MWD), and quadriceps strength in the first 26‐wk post‐transplant and examined what factors predict 6MWD recovery. All lung transplant recipients at a single institution between June 2007 and January 2011 were considered for inclusion. Lung function, 6MWD, and quadriceps strength corrected for body weight (QS%) were recorded pre‐ and two‐, six‐, 13‐, and 26‐wk post‐transplant. Fifty recipients, of mean (±SD) age 42 (±13) yr, were studied. Mean FEV1% and 6MWD improved from 26.4% to 88.9% and from 397 to 549 m at 26 wk, respectively (both p < 0.001). QS% declined in the first two wk but had improved to above pre‐transplant levels by 26 wk (p = 0.027). On multivariate analysis (n = 35), lower pre‐transplant exercise capacity and greater recovery in muscle strength explained most of the improvement in exercise capacity. Delayed recovery of exercise capacity after lung transplantation is unrelated to delay in improvement in graft function, but occurs secondary to the slow recovery of muscle strength. Our findings show that additional controlled trials are needed to better understand the influence of exercise rehabilitation on improvement in exercise capacity post‐transplantation. 相似文献
107.
Chambers DW 《The Journal of the American College of Dentists》2012,79(1):33-36
Legal practice, charity care, and professionalism are the outward signs of dental competence, symbolized by the white coat. Ethics, the transformation of character, is a reflection of the person wearing the white coat. Patients and others assume the first three from the title "doctor." What they want to know is what kind of person is wearing the white coat. 相似文献
108.
Kenan W. D. Stern Chen Chen Hillel W. Cohen Joseph Mahgerefteh Sarah A. Chambers Leo Lopez 《Pediatric cardiology》2016,37(6):1057-1063
Patient selection criteria for echocardiography with sedation in children are not well defined. We attempted to identify predictors of unplanned repeat echocardiography with sedation. This was a single-center, case–control study of echocardiograms performed in children aged 1–36 months. Cases underwent unplanned repeat examinations with sedation, while controls did not. Patient variables and study indications were compared. Logistic regression identified the most significant predictors. Cases (n = 104, median time to repeat echocardiogram 17 days, median age 12.9 months) were older than controls (n = 212, median age 5.0 months, P < 0.001). Significantly more cases than controls had structural cardiac disease (64 vs. 23 %) and anatomic complexity ≥moderate (38 vs. 5 %, P < 0.001 for both). Cases more often had Kawasaki disease (11 vs. 2 %), and controls more often had murmur (56 vs. 11 %, P < 0.001 for both). Logistic regression identified age 6 months to <2 years (OR 3.26, 95 % CI 1.70–6.28, P < 0.001), Kawasaki disease (OR 5.20, 95 % CI 1.46–18.50, P = 0.01), and known pre-echocardiogram anatomic complexity ≥moderate (OR 3.99, 95 % CI 1.64–9.66, P = 0.002) as significant risk factors. An indication for murmur was protective (OR 0.32, 95 % CI 0.13–0.76, P = 0.01). We identified several risk factors for unplanned repeat echocardiography with sedation in children, including age 6 months to <2 years, higher anatomic complexity, and Kawasaki disease. Murmur was a protective factor. These results may help pediatric echocardiography laboratories establish criteria for sedation. 相似文献
109.
Chambers CD Bellgrove MA Gould IC English T Garavan H McNaught E Kamke M Mattingley JB 《Journal of neurophysiology》2007,98(6):3638-3647
Intelligent behavior depends on the ability to suppress inappropriate actions and resolve interference between competing responses. Recent clinical and neuroimaging evidence has demonstrated the involvement of prefrontal, parietal, and premotor areas during behaviors that emphasize conflict and inhibition. It remains unclear, however, whether discrete subregions within this network are crucial for overseeing more specific inhibitory demands. Here we probed the functional specialization of human prefrontal cortex by combining repetitive transcranial magnetic stimulation (rTMS) with integrated behavioral measures of response inhibition (stop-signal task) and response competition (flanker task). Participants undertook a combined stop-signal/flanker task after rTMS of the inferior frontal gyrus (IFG) or dorsal premotor cortex (dPM) in each hemisphere. Stimulation of the right IFG impaired stop-signal inhibition under conditions of heightened response competition but did not influence the ability to suppress a competing response. In contrast, stimulation of the right dPM facilitated execution but had no effect on inhibition. Neither of these results was observed during rTMS of corresponding left-hemisphere regions. Overall, our findings are consistent with existing evidence that the right IFG is crucial for inhibitory control. The observed double dissociation of neurodisruptive effects between the right IFG and right dPM further implies that response inhibition and execution rely on distinct neural processes despite activating a common cortical network. 相似文献
110.
While fibre and wholegrains are often discussed simultaneously, they are distinct with the former classified as a nutrient and the latter as a food group that provides fibre, along with other important nutrients. Wholegrains are an integral part of a healthy, balanced diet and have been linked to several health benefits, including reduced risk of cardiovascular disease, type 2 diabetes and colorectal cancer. Yet consumption in the UK is low, and barriers to increasing wholegrain intake exist among the UK population. These include confusion around how much to consume, which foods contain wholegrains and how they are beneficial to health, acceptance of the organoleptic properties (e.g. taste, texture) of wholegrain foods, lack of knowledge about how to cook wholegrains and negative perceptions about starchy carbohydrates. The absence of a standardised wholegrains definition and a quantified wholegrain intake recommendation in the UK remains a challenge for consumers and industry, and may limit the impact of public health messages. The Healthgrain Forum has recently proposed definitions for ‘wholegrains’ and ‘wholegrain foods’ that are readily useable by the food industry and regulatory bodies. To help increase wholegrain intake in the UK, co‐operation and collaboration is required by stakeholders to educate consumers about wholegrains and inform initiatives. Food retailers have an important role to play in making wholegrains more accessible, convenient and palatable through actions such as product development and wholegrain labelling. 相似文献